To find the area of a rectangle, you can use the formula:
\[ \text{Area} = \text{Length} \times \text{Width} \]
Given that the length is 6 centimeters and the width is 3 centimeters, you can substitute these values into the formula:
\[ \text{Area} = 6 , \text{cm} \times 3 , \text{cm} = 18 , \text{cm}^2 \]
Therefore, the area of the rectangle is \( 18 , \text{cm}^2 \).